http://www.460ford.com/forum/showthread.php?t=138991
I see in the pictures there is a plate between the bellhousing and engine, however the only bolts appear to be threaded into the block.
My Lakewood has additional bolts and nuts, spaced between the bolts threaded into the block, clamping the engine plate and bellhousing. These help contain the flywheel/clutch pieces between the plate and bellhousing if the block breaks.
This makes me think the bellhousing on the dyno was not SFI approved. I was surprised there was no mention of the bellhousing in the thread.
Rodger